foo.cc: In function 'int main()':
foo.cc:8:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  { scanf("%d%d%d%d", &a[i],&b[i],&x[i],&y[i]);
    ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:7:15: warning: 'n' is used uninitialized in this function [-Wuninitialized]
  for(int i=1;i<=n;i++)
              ~^~~
foo.cc:13:1: warning: 'X' may be used uninitialized in this function [-Wmaybe-uninitialized]
 if( X<=a[i]+x[i]&&X>=a[i]&&Y>=b[i]&&Y<=b[i]+y[i])
 ^~
foo.cc:13:26: warning: 'Y' may be used uninitialized in this function [-Wmaybe-uninitialized]
 if( X<=a[i]+x[i]&&X>=a[i]&&Y>=b[i]&&Y<=b[i]+y[i])
     ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~

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